The present invention generally relates to fuel-fired heating appliances and, in a preferred embodiment thereof, more particularly relates to a fuel-fired water heater having a specially designed malfunctioning component diagnostic system incorporated therein.
As conventionally manufactured, a fuel-fired water heater typically comprises an insulated tank for containing water to be heated, and a fuel-fired combustion system for transferring heat to the water to maintain it at a predetermined heated temperature for on-demand delivery from the tank to various items, such as faucets, shower heads, dishwashers and the like operatively connected to the water heater. Various electrically actuatable components are incorporated into the overall water heater apparatus to automatically add heat to the tank water when its temperature falls below the heated set point temperature.
For example, a thermostat is used to sense a drop in tank water temperature and responsively activate an ignition controller which sequentially opens pilot and main portions of a fuel valve which are connected to a burner structure, and ignites the fuel discharged from the burner. Hot combustion products from the burning fuel are flowed through a flue structure extending through the tank water to thereby add combustion heat to the water and return it to its setpoint temperature at which point the thermostat deactivates the ignition controller to terminate the flow of fuel to the burner apparatus.
Like all mechanical and electrical components, the operational and control components in a fuel-fired water heater are subject to failure and malfunction which ends the water heater's ability to maintain the tank water at the desired heating setpoint temperature. When such component failure or malfunction occurs, all that the typical water heater owner is usually aware of is that hot water is no longer available from the unit. Accordingly, a water heater service technician (such as a plumber) is typically called in to fix the water heater.
While a water heater service technician may carry various diagnostic tools, such as voltage probes and the like, which may be used to individually check the various water heater components for proper operation, a very common repair mode is to simply leave the diagnostic tools in the truck and begin to replace the individual water heater components until the water heater is able to heat its tank water again. This common repair technique, of course, tends to be both inefficient and expensive if the first replaced component is not the failed one. Oftentimes, several perfectly good components are needlessly replaced before the water heater is operative again.
From the foregoing it can readily be seen that a need exists for an improved technique for diagnosing a problem in a water heater system in a manner such that a failed or malfunctioning component can be readily identified and efficiently replaced, adjusted or repaired. It is to this need that the present invention is directed.